The court's 7-0 ruling concluded that the constitutional
amendment was properly put to voters in a statewide referendum in
2006. Justices rejected a lawsuit that claimed the amendment
violated a rule limiting constitutional amendments to a single
subject.

The question asked voters whether marriage should be limited to
one man and one woman and whether to outlaw any "legal status
identical or substantially similar" to marriage for same-sex
couples. Nearly 60 percent of voters approved.

The lawsuit, filed by a voter opposed to the amendment, argued
that the amendment consisted of two questions that could have
reached different results had they been asked separately: whether
to ban gay marriage, and whether to ban civil unions. Polling at
the time showed much greater support for civil unions.

Writing for the majority, Justice Michael Gableman rejected that
argument. He said both parts of the question had the same general
subject: preserving the current legal definition of marriage as
between one man and one woman.

"The first sentence preserves the one man-one woman character
of marriage by so limiting marriages entered into or recognized in
Wisconsin," Gableman wrote. "The second sentence, by its plain
terms, ensures that no legislature, court or any other government
entity can get around the first sentence by creating or recognizing
'a legal status identical or substantially similar to that of
marriage'."

Gableman said his opinion was not a decision on whether the
amendment "is good public policy or bad public policy" and should
have no impact on its interpretation or application. He said
decades of court precedent related to constitutional referendum
questions guided his conclusion.

He said past Supreme Court decisions gave the Legislature
"considerable discretion" in drafting and submitting
constitutional amendments for approval. Lawmakers have to approve
the referendum in two straight legislative sessions before it goes
on the statewide ballot.

"The Legislature may submit multiple propositions within one
proposed amendment so long as those propositions tend to effect and
carry out one general purpose and are connected with one subject,"
Gableman said, citing earlier cases.

Attorney General J.B. Van Hollen had defended the amendment,
which he called the "will of the people." He argued the voter who
filed the lawsuit, William McConkey of Baileys Harbor, did not have
legal standing to bring the lawsuit. Van Hollen argued McConkey
suffered no injury because he would have voted "no" on both
propositions.

Gableman agreed McConkey's "alleged injury is difficult to
define," but said the court decided to address the merits because
of the case's significance.

A Dane County judge had dismissed McConkey's lawsuit in 2008,
and the court agreed to hear the case last year. The decision to
uphold the amendment is not surprising since the court is widely
seen as having a conservative majority following the election of
Gableman in 2008.

But the unanimity of the court, which is often deeply divided on
controversial matters, was striking.

The decision is the second setback for gay rights advocates in
Wisconsin in one week. Last week, an appeals court ruled that a
woman who raised two adopted children in a same-sex relationship
for years was not a "parent" under Wisconsin law.